How to weight paint character whose mesh is in several [joined] pieces?
OK!  So, cautionary tale for other animators: If you redo your IK bones 50 times, make sure that each time you uncheck "deform", otherwise good luck figuring out what portions of your mesh you are going to get unwanted vertex weights for. In this example, the IK bones at the heels painted the heels (unwanted), but the pole targets offset from the knees painted only the mustache (for some reason, also unwanted). Beware!